Line-space mechanism.



A. C. ROEBUCK.

LlNE SPACE MECHANISM.

APPLICATION FILED 0:50.15. 1913.

L243, 1 1 G, Patented 00$. 16, 1912.

' r 2 SHEETS-SHEET I.

A. C. ROEBUCK.

LINE SPACE MECHANISM.

APPLICATION HLED DEC-15 H3- 1 243, 1 1 Patented 0st. 16, 191?.

2 SHEETSSHEET 2- Ill FFIQE.

ALVAH O. ROE-BUCK, OF WOODSTOCK, ILLINOIS, ASSIGNOR T0 WOODSTOCK TYPEWRITER COMPANY, OF WOODSTOCK, ILLINOIS, A CORPORATION OF ILLINOIS.

LINE-SPACE MECHANISM.

Specification of Letters Patent.

Patented Oct. 16, 1917.

To all whom it may concern:

Be it known that I, ALvAH C. RoEBUoK, a citizen of the United States, residing at Woodstock, in the county of McI-Ienry and State of Illinois, have invented certain new and useful Improvements in Line-Space Mechanism, of which the following is a specification.

This invention relates to typewriters, and more particularly to the mechanism by means of which the written lines are spaced apart. The principal object of the invention is to provide an improved mechanism of this class which is simple and durable in construction and effective and efficient in operation.

A further object of the invention is to provide improved means for varying the space between the written lines, and for braking the platen when the ordinary line space feed is made andeffected.

For the attainment of these ends and the accomplishment of other new and useful objects, as will appear, the invention consists in the features of novelty in the construction, combination and arrangement of the several parts generally shown in the accompanying drawings and described in the specification but more particularly pointed out in the appended claims.

In the drawings;

Figure 1 is a plan view of a mechanism constructed in accordance with the princi ples of my invention and applied to one end of a typewriter carriage frame in connection with the platen thereof.

Fig. 2 is a sectional view taken on the line 22 of Fig. 1.

Fig. 3 is an end elevation of the mechanism shown by Fig. 1, some of the parts being omitted for clearness.

Fig. 4 is a detail view similar to Fig. 2, with the detent thrown out and the braking spring thrown in.

Fig. 5 is a detail View taken on the hne 55 of Fig. 3, and

Fig. 6 is a detail front elevation with some of the parts omitted for clearness.

In most typewriter mechanisms the return of the carriage to starting position or toward the right, and the line spacing movement of the platen is efiected simultaneously by the movement of the hne space lever.

In the present exemplification of my 111- vention the numeral 10 designates generally one end plate of a typewriter carriage in which is mountd a platen 11 with supporting heads at the ends. The axle of the platen passes through the heads and is extended beyond the end plate and is provided with a knurled adjusting wheel or knob 12 by means of which the platen may be manually rotated in either direction. The end plate 10 is, of course, connected to a corresponding end plate at the other end of the carriage by means of rods 13.

Mounted upon the axle or aflixed adjacent the end of the platen 11 in any well known manner is a toothed wheel 14, and also freely mounted upon the same axis is an arm 15 formed with an over-hanging projection 16. Pivotally connected to this arm and disposed without the periphery of the toothed wheel 14 is a pawl 17 adapted to engage the teeth of the wheel 14, a spring 18 being disposed between the projection 16 and the pawl and tending to press it in engagement with the toothed wheel. Rotatable about the same axis as the arm 15, preferably upon the axle of the platen, is an adjustable member 19 formed at its upper end with a projection 20. The pawl 17 is provided with an arm 21 secured or formed integral therewith which is adapted to engage the projection 20 upon the rearward movement of the pawl.

To effect the movement of the pawl a line space lever 22 is pivotally connected by means of a bracket 23 to the plate 10, one arm of the lever being formed with a fingerhold portion 2 1, and the other arm 25 of the lever being connected by means of a link 26 with the arm 15. The movement of the lever 22 toward the end plate 10 causes the rearward movement of the arm 25 and the corresponding movement of the link 26 and the pawl 17 connected thereto. As soon as the pawl is moved rearwardly so that the arm 21 is out of engagement with the abutment or projection 20 the spring 18 presses it in engagement with the teeth of the wheel 14. To limit the forward movement of the pawl 17 a stop 27 is provided, and the bracket 23 is formed with a projection 28 in which is threaded an adjustable pin 29 with which an adjustable pin 30, connected to the arm 25 of the line space lever 22, is adapted to engage. The normal position of the pawl 17 is with the arm 21 against the abutment or projection 29 with the pawl held out of engaging position with respect to the toothed wheel 14 and with the spring 18 compressed. In this position the arm 24 of the lever 22 is furthermost from the end plate and is held in such position by means of a spring 31, which is of sufficient strength to overcome the tension of the spring 18 and to hold the arm 21 of the pawl firmly in engagement with the abutment 20. The extent of the line' space movement is varied by means of a gage plate 32 formed integral with or secured to the end plate 10 and provided with a plurality of perforations 33. The adjustable member 19 is formed with a-projection 34 bent over at the extremity to embrace the plate 32, and mountedin the turned over portion is a casing 35 in which is disposed a headed pin 36 and a spring 37 tending to press the pin inwardly in engagement with the perforations 33 of the gage plate 32. The outer end of the pin projects through the casing 35 and is provided with a knurled nut 38 byv means of which the pin 36 can be raised out of engagement with any one of the holes 33 against the tension of the spring 37. The adjustment of this member 19, by means of the gage plate and the pin 36, varies the position of the abutment 20 and varies the distance of the return movement of the pawl 17, whereupon the forward movement of the pawl will be,limited to a corresponding extent and the movement of the platen will be varied accordingly. Ordinarily the graduations of the gage plate correspond to different line spacing distances upon the platen. In order to hold the platen in any adjusted position a detent roller 39, adapted to engage the teeth of the wheel 14, is mounted upon an arm 40 pivoted upon a rod 41 and with a spring 42 tending to press the arm upwardly and the detent roller 39 into engagement with the teeth of the Wheel 14. Rotatably mounted in the plate 10 adjacent the arm 40 is a member 43 carrying a pin 44 adapted to engage the extremity of the arm 40. The movement of this member 42 is limited by a pin 45 secured to the plate 10 which engages a shouldered portion 46 of the member. In one position, as shown by Fig. 2, the pin 44 permits the arm 40 to move upwardly under the action of the spring 42 so that the detent roller 39'engages with the toothed wheel 14. In the other position, as shown by Fig. 4, the member 43 is turned so that the pin 44 engages the arm 40 and holds the detent roller 39 out of engagement with the toothed wheel 14. A knurled nut 47 is provided for rotating the member 43 and it is located on the outside of the plate 10 so that ready access may be had to it.

Also carried by the arm 40 and preferably secured to projections 48 formed integrally therewith is a brake spring 49 which is adapted to bear against the platen 11 and preferably in the groove 50 formed in one supporting head of the platen. This brake spring 49 is so disposed that when the detent roller 39 is in engagement with the toothed wheel 14, the brake spring is out of engagement, and when the detent roller is out of engagement, as shown by Fig. 4, the brake spring is in engagement with the groove 50. The object of this construction is to provide a brake for the platen to hold it yieldingly in position when the detent roller 39 is out of engagement therewith At this time the platen 11 may be rotated in either direction by means of the hand wheel 12 against the tension of the brake spring, the latter being of suflicient strength only to hold the platen from free rotation and ofi'ering no material opposition to the rotation of the platen in either direction.

In operation the line space distance is varied by means of the gage plate 32 and the adjustable pin 36, and the line space movement of the platen is eifected by means of the lever 22, as above set forth. The return of the pawl 17 against the abutment 2O forces it out of engagement with the toothed wheel 14 against the tension of the spring 18, and it remains out of engagement until the line spacelever 22 is again actuated. The operation of the detent roller and the brake spring 49 has been clearly set forth.

What I claim is:

1. In line space mechanism, the combination with a platen having supporting end heads and a ratchet wheel, means to engage the wheel and rotate the platen, a roller to engage the ratchet wheel, a brake for engaging one platen head consisting of a straight spring bar, and a single pivoted arm on which the roller and the spring bar are both mounted below the platen head and movable to apply the brake when the roller is withdrawn from the wheel and to engage the roller with the wheel when the brake is withdrawn.

2. In line space mechanism, a platen having end heads, a ratchet wheel and an axis on which it is rotated, means to engage the wheel to rotate the platen, a roller to engage the teeth of the ratchet wheel, a brake for one platen head consisting of a straight spring bar, and a single pivoted and springpressed arm disposed entirely below the platen head on which both the roller and the spring bar are mounted, the arm being normally held by its spring so that the roller is in engagement with the 'teeth of the ratchet wheel but movable to disengage the roller from such engagement and to move the brake against the head of the platen.

3. In line space mechanism, the combination with a platen having a ratchet wheel and headed ends, of means to engage the wheel and rotate the platen, a roller to engage the teeth of the ratchet wheel, a brake consisting of a straight spring bar to engage the platen head at one end, a sin is pivoted arm on which both the roller an the spring bar are mounted and with which they are movable so that either one but not both is in operative engagement, a spring-tending to press the arm so that the roller engages the toothed wheel, and rotatable means at the free end of the arm to move the arm so that the roller is out of engagement with the wheel and the brake is in engagement with the platen head.

4. In line space mechanism, the combination with a platen having a ratchet wheel and headed ends, end plates on which the axle is mounted, means operative on the inside of one of the end plates to engage the wheel and rotate the platen, a roller to engage the teeth of the ratchet wheel, a brake to engage one head consisting of a straight spring bar, a single spring-pressed arm pivoted at one end on .the inside of one of the end plates upon which both the roller and the brake bar are mounted, and means to control the position of the arm comprising a rotatable member having an eccentric pin inside of the end plate to engage the free end of the said pivoted arm, and a knurled nut on the outside of the end plate by means of which the rotatable member is operated to move the arm so that either the brake or ment.

5. In line space mechanism, the combination with a toothed platen wheel having a grooved platen head at one end, spring pressed means for engaging either the toothed wheel to limit the rotation thereof to a step by step movement or to frictionally engage the platen head, an adjustable abutment adjacent the wheel periphery, a manually operable arm pivoted upon the wheel axis, a spring pressed pawl adapted to engage the teeth of the wheel and having a tail piece to engage the said abutment for throwing the pawl out of engagement in one position of the arm, and means tending V to press the arm in the position to throw the pawl out of engagement with the wheel.

6. In line space mechanism the combination with a toothed platen whee having a the roller is in operative engage being pressed into engagement with ,the teeth of the wheel as soon as the tail piece is moved away from the abutment, and a fixed stop to limit the movement of thepawl and of the arm in a direction away from the abutment.

7. In line space mechanism, the combination with a toothed wheel, of a'pawl movable to engage the teeth of the wheel for rotating it in a single direction, a pivoted line space lever, means connecting the lever and the pawl comprising a link, a threaded projection, a pin adjustable in the projection, means to predetermine the extent of movement of the wheel, and an adjustable pin in one arm of the lever adapted to engage the other adjustable pin for accurately limiting the movement of the line space lever.

8. In line space mechanism, the combination with a carriage end plate, of a platen rotatabl mountedt erein, atoothed wheel connecte to the platen, a pawl pivotally mounted adapted to engage the teeth of the wheel, a bracket secured to the plate having a threaded projection thereon, a lever adapted to move the pawl and limited in one direction of movement by the projection of said bracket, and an adjustable abutment to out of engagement with the wheel, the pawl. 1 

